Exposure to UV rays from sunlight is a major cause of skin erythema, edema, freckles or skin cancer. Recently, many studies on various skin diseases caused by UV rays have been actively conducted.
Generally, UV rays are classified according to wavelength into UV-C (240-280 nm), UV-B (280-320 nm) and UV-A (320-400 nm). UV-C radiation does not reach the Earth's surface because it is absorbed by the ozone layer, but UV-B penetrates the epidermis so that it causes erythema, freckles, edema, etc. It is known that UV-A penetrates into the dermal layer of the skin to cause skin aging and skin irritation, thereby stimulating skin cancer, wrinkles and melamine formation.
Public interest in products for protecting the skin from the sun has significantly increased and, as a result, UV blocking products having various sun protection factors (SPFs) have appeared in the market. UV blocking products are generally prepared in the form of cream or lotion and can be classified, according to the composition of the inner phase and outer phase of emulsion, into W/O type (water-in-oil) and O/W type (oil-in-water).
UV blocking products have been used mainly in the summer season. However, recently, as life styles have changed due to an increase in the number of peoples enjoying leisure and as the recognition of the harmfulness of UV radiation has increased, the demand for the use of UV blocking products in all four seasons, rather than only in summer, has increased. Accordingly, the consumer demand has increased for UV blocking products having increased usability and convenience to use.
In the prior art, UV-blocking W/O or O/W emulsion products have been used in the state in which they are contained in tube or pump containers in order to set the viscosity and to improve the usability. However, these products are relatively inconvenient to carry and use, thus causing inconvenience in make-up correction. Particularly in summer, cosmetic products that lower the skin temperature to give a cold feel are more preferred. However, because the compositions are applied to the skin by hand, cosmetic products comprising cosmetic compositions in tube or pump containers cannot give a cold feel due to the heat of hand used to apply them. In addition, after the use of the cosmetic compositions, the hand should be washed to remove the contamination and stickiness caused thereon by applying the cosmetic compositions.